2. Slice french bread in thick slices, like Texas toast garlic bread style. Arrange slices on top of cookie sheet.
3. In a mixing bowl, mix shredded cheese, melted butter, mayo, chopping green onions, and sliced mushrooms. Season to taste with garlic powder. I personally love a lot of garlic, but this can be altered to taste.
4. Spread mixture over top of bread pieces, making sure not to put too much on each piece as cheese will melt and spread. Top pieces with black olives if desired.
5. Bake bread for 10 to 15 minutes, until cheese is bubbly, but not overly browned.